Valid Palindrome

 

class Solution {
public:
    bool isPalindrome(string s) {
        int strLen = s.size();
        int pos_h = 0;
        int pos_t = 0;
        char *copy = new char[strLen];
        int num = 0;
        for(int i=0;i<strLen;i++)
        {
            if(s[i] >= 65 && s[i]  <= 90 || s[i] >= 48 && s[i] <= 57)
              {
                  *(copy+num) = s[i];
                  num++;
              }
              else if(s[i] >= 97 && s[i]  <= 122)
              {
                  *(copy+num) = s[i] - 32;
                  num++;
              }
        }
       if(num == 0 || num == 1)
            return true;
        pos_h = 0;
        pos_t = num - 1;
        for(int i=0;i<num/2;i++)
            {
               if(copy[pos_h] != copy[pos_t])
                    break;
               pos_h++;;
               pos_t--;
            }
            if(pos_h < pos_t )
                return false;
            else
                return true;
    }
};